Each residence set up for phone service usually has telephone distribution wires coming in from a central office or the like with the distribution wires terminating under screw terminals in a conventional telephone terminal block. Typically, wires in a telephone cord from a station set or the like are spade lugged and connect directly to the screw terminals in the block. A protective insulative cover secures over the block after the connections are made. Each time connection or disconnection of a station set is desirable, the cover must be removed to connect or disconnect the telephone cord wires.
A growing number of telephones, and especially customer-owned telephones, are manufactured with cords having modular plugs. Hence, increasingly, terminal blocks must be converted to modular jacks with modular jack converting assemblies. Also, increasingly, customers are installing their own station sets.
One modular jack converter which is being used includes a modular jack affixed to a converter housing similar to the conventional cover. Leads in the converter housing connect at one end to contacts in the modular jack and at the other end to the screw terminals in the terminal block via spade-lugged ends. This prior art converter requires a customer-installer to unscrew the screw terminals to secure the converter leads and involves physical tampering of already-made connections. This can cause accidental dislodging of the incoming distribution wires and lead to confusion especially to those unfamiliar with terminal blocks. Also, tampering with the screw terminals can expose a customer-installer to potential shock hazards. Hence, there is need for modular jack converting assemblies that are easier for customers to install.
Another modular jack converter which has been developed for converting a terminal block and is easy to install is disclosed in Anderson U.S. Pat. No. 4,071,696. In Anderson, helical spring contacts in the jack are positioned in a predetermined arrangement and physically contact the assigned screw terminals upon attachment of the jack converter to the terminal block.
However, terminal blocks found in customers' residences vary in age and condition. In some terminal blocks, the screw terminals are corroded or otherwise covered with contaminating particles so that mere physical contact does not result in reliable electrical connection. In addition, the incoming distribution wires, which have been assigned a particular colored insulation, according to a predetermined arrangement, are not always connected to their normally designated screw terminals or to the proper connections at the central office.
Hence, one object of this invention is to develop a modular jack converting assembly which minimizes the effect of the corroded or contaminated surfaces of screw terminals on electrical connection and which includes screw-engaging connectors capable of penetrating most corroded or otherwise contaminated screw terminal surfaces.
Another object is that the modular jack converting assembly minimizes physical tampering on the part of a customer-installer with the screw terminals of the terminal block to reduce confusion and to prevent potential shock hazards.
A further object of this invention is that the modular jack converting assembly is quick and easy to install and inexpensive.